THE BUTTERFLY. 



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you can see all the parts of the butterfly shining through 

 it. Finally it splits in several places, and the butterfly 

 crawls out and begins to dry off the oil in the sun. At 

 first the wings look small and limp, but as soon as the 

 butterfly breathes they swell out and get larger, as the 

 air-tubes (tracheae) in the wings become filled with 

 air. In about an hour the new butterfly is all nice and 

 dry, beautifully painted and polished, and away it goes 

 skimming through the air in search of sweet syrup to 

 sip from the cup of some flower. Now our friend is 

 called an imago, or image. In the first place he wore a 

 mask, hence his name larva ; then he went to sleep in 

 his homespun blankets like a baby in its cradle, so he 

 was called a pupa. Now he has come forth an image, a 

 perfect image of the butterfly, so now he is an imago. 

 Almost all insects, the class of animals to which our 

 butterfly belongs, pass through these three stages of life. 

 There is one thing to remember about this imago, it 

 never grows after it is born, so none of the little flies 

 and moths that you see ever get to be big ones. The 

 first things you are likely to notice about the butterfly 

 are the wings. They are very showy and most beauti- 

 ful too, but we will not begin to study them just yet. 

 First of all you can see that there are three distinct 

 parts to the butterfly's body — a head, a breast, or tho- 

 rax, and a body, or abdomen. The thorax and abdo- 



